How does an electron in orbit not accelerate towards a proton in an atom?

[kshah93]

If the proton in the nucleus of, say a hydrogen atom, exerts an attractive force on an electron that is in orbit, why doesn't the electron move towards the proton? And does this have anything to do with the electric force being the centripetal force?

 

[94JZA80]

does this have anything to do with the electric force being the centripetal force?

no, it doesn't. that is, you cannot apply the classical mechanics of gravitating bodies to an electron and the nucleus it "orbits"...and i use quotations b/c en electron does not orbit the nucleus of an atom in the traditional sense of a planet orbiting a star for instance. quantum mechanics are required to explain why an electron doesn't plunge radially into the nucleus of an atom, and i do not pretend to know the details myself...i have a very basic understanding of it, and as such could not begin to explain it beyond what I've already said. with that, i did notice another recent thread started by someone who wanted to share what he felt was a very good short video on quantum physics. whether that's true or not, i don't know, but the first few minutes of the video explain (or perhaps under-explains) in layman's terms why an electron does not spiral into the nucleus of an atom via a traditional orbit. here's the thread:

https://www.physicsforums.com/showthread.php?p=3240077#post3240077"

 

[ank160]

no, it doesn't. that is, you cannot apply the classical mechanics of gravitating bodies to an electron and the nucleus it "orbits"...
QUOTE]

..but classical mechanics can be apllied to earth-monn system, right. Then why doesn't moon collapse on the Earth despite the fact that it is constantly pull by eart diue to its magnetic pull.

 

[Khursed]

no, it doesn't. that is, you cannot apply the classical mechanics of gravitating bodies to an electron and the nucleus it "orbits"...
QUOTE]

..but classical mechanics can be apllied to earth-monn system, right. Then why doesn't moon collapse on the Earth despite the fact that it is constantly pull by eart diue to its magnetic pull.

It's vectors.

The moon is actually moving away from the Earth extremely slowly.

An orbit is actually falling toward and away from an object at the same rate. If you are moving away a tiny bit faster then falling toward, you will one day escape, if you move toward a tiny bit faster then away, you will eventually connect.

BTW it has nothing to do with magnetic pull when it comes to the earth-moon orbit, its gravity.

If for example the Earth was positive, and the moon negative in any meaningful way, the two object would collide faster then you can imagine due to electro-magnetism's incredibly stronger nature compared to gravity.

As I understand it, the reason the electron and proton don't combine is quantum related in this way, first the electron is not really in orbit around the proton of an hydrogen atom, or any other atom like we envision the moon around the earth. The electron, or electrons are in a shell of probalistic distribution around the nucleus. Since the uncertainty principle dictates that we can not know both the location and speed of a particle, this is why the electron can never be verifiably positioned around the nucleus.

So, the whole "lose energy and fall upon the proton" isn't as straightforward as that, secondly, the mass of the proton and the electron are less then the neutron. This has for consequence that you would need to supply energy to make both of them collapse together. The electromagnetic force isn't sufficient for that to happen. So an electron that is in an orbital cloud above a nucleus, can not just lose energy and merge with the proton.

The best known method of combining proton and electron is the massive energy of a super-nova that collapses the iron core of a super giant star into a super dense neutron star. When the star goes super-nova, the energy liberated is stupenduous, thus enabling the combination of proton and electron, thus forming a neutron star.

I hope I managed to answer, within my limited ability, your question.